extern void invert_address(uschar *, uschar *);
extern int ip_bind(int, int, uschar *, int);
-extern int ip_connect(int, int, uschar *, int, int);
+extern int ip_connect(int, int, const uschar *, int, int);
extern int ip_connectedsocket(int, const uschar *, int, int,
int, host_item *, uschar **);
extern int ip_get_address_family(int);